My very first time starting seeds cabbage disease

[Smart Red]

one thing not mentioned is black spot -- a virus often found in the soil. it could splash up when the plants are watered. as quickly as the sprouts are growing, leaves may grow and holes show up where leaf material was damaged.
not saying thats your problem, but if youre not seeing bugs?

 

[ducks4you]

I would suggest that you replant and use one of those starter gardens, the ones with the cells and the plastic lid. TAPE THE LID ON SECURELY after you plant and get the soil moist, NOT soaking wet, then MAKE SURE THAT YOU HAVE A GOOD LIGHT SOURCE. It's almost time to put the seeds in the ground, but, if you are like me, you will want to be able to start seeds inside in the future. I also suggest that you take good photos of ALL of your houseplants and determine what bugs are on THEM, and that or those will be your culprits.

 

[catjac1975]

Those big bites look like slug bites. I would replant unless youu have seen an improvement.

 

[thistlebloom]

The blackspot disease I have seen makes pretty big spots with yellowing around the edges. Those little pepper black spots don't look like it to me. Can you brush or wipe them off (like insect excrement) or are they actually a damaged part of the leaf?